Tool control system and method

• US 3,963,364 A
• Filed: 06/14/1974
• Issued: 06/15/1976
• Est. Priority Date: 01/11/1963
• Status: Expired due to Term

• Current Assignee: Jerome H. Lemelson
• Original Assignee: Jerome H. Lemelson
• Inventors: Lemelson, Jerome H.
• Primary Examiner(s): Simpson, Othell M.
• Assistant Examiner(s): Briggs, William R.
• Application Number:
  US05/479,515
• Time in Patent Office: 732 Days
• Field of Search: 408/6, 408/8, 408/3, 408/11, 408/13, 250/224, 250/235, 356/69, 356/168, 356/237, 356/167, 340/267 R
• US Class Current: 408/8
• CPC Class Codes: B23B 49/001 Devices for detecting or indicating failure of drills
• CPC Class Codes: B23P 25/006 Heating the workpiece by laser during machining
• CPC Class Codes: B23Q 17/0909 Detection of broken tools
• CPC Class Codes: G05B 19/18 Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form G05B19/418 takes precedence
• CPC Class Codes: G05B 19/401 characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes G05B19/19 takes precedence
• CPC Class Codes: G05B 19/404 characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia G05B19/19, G05B19/41 take precedence
• CPC Class Codes: G05B 2219/35554 Mirror, other conversions
• CPC Class Codes: G05B 2219/36503 Adapt program to real coordinates, software orientation
• CPC Class Codes: G05B 2219/36504 Adapt program to real coordinates, shape, dimension of tool, offset path
• CPC Class Codes: G05B 2219/37032 Generate vibrations, ultrasound
• CPC Class Codes: G05B 2219/37228 Tool inspection, condition, dull tool
• CPC Class Codes: G05B 2219/37245 Breakage tool, failure
• CPC Class Codes: G05B 2219/37345 Dimension of workpiece, diameter
• CPC Class Codes: G05B 2219/37351 Detect vibration, ultrasound
• CPC Class Codes: G05B 2219/37357 Force, pressure, weight or deflection
• CPC Class Codes: G05B 2219/37405 Contact detection between workpiece and tool, probe, feeler
• CPC Class Codes: G05B 2219/37409 Measure different pressure of fluid flow on contacting surface
• CPC Class Codes: G05B 2219/37415 By cutting light beam
• CPC Class Codes: G05B 2219/37417 By linear varying electrical signal
• CPC Class Codes: G05B 2219/37418 By capacitive means
• CPC Class Codes: G05B 2219/37559 : Camera, vision of tool, compute tool center, detect tool wear
• CPC Class Codes: G05B 2219/40383 : Correction, modification program by detection type workpiece
• CPC Class Codes: G05B 2219/49134 : Clamp, keep positioned slide, workpiece stationary during machining
• CPC Class Codes: G05B 2219/49302 : Part, workpiece, code, tool identification
• CPC Class Codes: G05B 2219/50031 : Zero setting, go to reference with gauge
• CPC Class Codes: G05B 2219/50063 : Probe, measure, verify workpiece, feedback measured values
• CPC Class Codes: G05B 2219/50139 : Calibration, setting tool after measurement on tool
• CPC Class Codes: G05B 2219/50145 : Tool setup manual, preset of the machine
• CPC Class Codes: G05B 2219/50249 : Tool, probe, pen changer
• CPC Class Codes: G05B 2219/50294 : Tool offset length by going to a reference and recording distance
• CPC Class Codes: G05B 2219/50296 : Tool offset by verifying piece and registrating errors
• CPC Class Codes: G05B 2219/50315 : Selfcorrecting by measurement during machining
• CPC Class Codes: G05B 2219/50379 : Workpiece detector, sensor
• CPC Class Codes: Y10T 408/16 : with control means energized in response to activator stimulated by condition sensor
• CPC Class Codes: Y10T 408/21 : with signal, indicator, illuminator or optical means

Abstract

An apparatus and method are provided for controlling automatic machines such as a metal cutting tool to perform predetermined operations on a work-piece. Different means are provided for sensing the workpiece as to shape, diameter or length to determine the degree of its adjustment or wear. An inspection device or probe is provided with a transducing means operable to generate signals which are indicative of workpiece dimensions and or location. The signals are analyzed by means of computing circuits which generate control signals for performing such functions such as cycle starting, correction of tool adjustment and varying the control program to permit the performance of predetermined operations on the work by the tool.

Claims

1. A method of controlling a machine tool comprising:

disposing a sensor in scanning relationship with a tool defining part of a production machine wherein said tool part is operable to become varied in its configuration during its operation on a workpiece,

effecting relative movement between said tool part and said sensor to permit said sensor to scan said tool part and to generate an output signal which is indicative of the configuration of said tool part,

comparing said output signal derived in scanning said tool part with a reference signal representative of a desired tool configuration,

generating a difference signal which is indicative of the difference between said sensor output signal and said reference signal and a variation in the configuration of said tool from a standard configuration, and

applying said difference signal to control the operation of said tool whereby said tool predeterminately performs on said workpiece.

2. A method in accordance with claim 1 wherein said relative movement between said tool part and said sensor is effected while said tool performs an operation on said workpiece.

3. A method in accordance with claim 1 wherein said tool part includes a rotary cutting means and said sensor is operable to scan at least a portion of said rotary cutting means for generating said output signal indicative of the configuration thereof.

4. A method in accordance with claim 3 wherein said rotary cutting means of said tool includes at least one cutting edge subject to wear during the operation of said tool and said sensor is operable to scan said cutting edge and to generate output signals which are indicative of the condition of said cutting edge during the scanning operation.

5. A method in accordance with claim 3 wherein said sensor is operable to detect variations in the diameter of said rotary cutting means and to generate output signals which are indicative of said variations in diameter.

6. A method in accordance with claim 1 wherein said tool part comprises a cutting means at the end thereof and wherein the length of said tool part which includes said cutting means may vary with wear or variations in the mounting thereof on said machine, said method including effecting relative movement between said sensor and the end of said tool part to permit said sensor to scan and detect variations in the length of said tool part and effect said variations in said output signal thereof which are representative of the variations in the length of said tool part.

7. An automatic production machine for performing preprogrammed operations on work comprising in combination with a tool head and a spindle rotatably supported by said tool head, a cutting tool supported by said spindle and means for power rotating said spindle to permit said cutting tool to machine work which is predeterminately positioned with respect to said production machine, an inspection transducer supported by said tool head and operable to detect variations in the configuration of said tool as said cutting tool rotates and operates on work, means for generating signals on the output of said transducer, means for receiving said signals generated by said transducer and means for utilizing said received signals for controlling the operation of said tool on said work.

8. An automatic production machine in accordance with claim 7 wherein said transducer comprises a radiation generating means operable to generate and direct scanning radiation in the direction of said cutting tool and means supported by said tool head for receiving said scanning radiation after it has been modulated by said cutting tool and for converting said received radiation to electrical signals indicative of the condition of said cutting tool.

9. An automatic production machine in accordance with claim 7 wherein said transducer includes means for generating and transmitting vibrational energy through said spindle and said cutting tool.

10. An automatic production machine in accordance with claim 9 wherein said means for generating vibrational energy is operable to generate vibrations in said tool of sufficient intensity to enhance the cutting action of said cutting tool.